Thank you for all the comment. Actually, I currently doing research on web servers (tomcat, websphere, weblogic, SJSWS).
I like to choose websphere how you think so? because my database is informix and OS is sunOS and websphere is support J2EE also.
I made much better experience with open-source products than with commercial products (upgrade, bugfixing, compatibility etc.). Especially if you are a newbie and have no paid support from the manufacturer (IBM, Broadvision, BEA), it's so much more complicated and most likely you will fail.
Many people forget during evaluation that sooner or later you need to implement non-out-of-the-box functionality, and then it's worth gold if you don't have a proprietary system.